Where has the love gone in the market for tree-hugging cars? Forget old-fashioned muscle car wars; those tire-smoking stop-light rivalries between Mustangs and Camaros have nothing on the slap fest that's currently taking place in the green (and mean!) world of plug-in hybrids. Ford has just announced its upcoming C-Max Energi plug-in hybrid will have an electric-only range of approximately 20 miles, an EV top speed of 85 mph, and fuel economy average of 47-mpg in both city and highway driving. The American automaker handily pointed out that these figures are better than the EV range and electric top-speed of the plug-inPrius, along with besting the fuel economy figures of the Prius v wagon.

To Toyota's credit, there is a bit of fuzzy math at work here. Ford also recently touted the C-Max Energi – which is due to go on sale in 19 markets this fall and nationwide in 2013 – as the cheapest plug-in hybrid on the market. That's true, so long as you factor federal and state tax credits into the C-Max Energi's base price of $33,745. Without the incentives factored into the price, the base Prius Plug-In Hybrid is actually about $1,000 cheaper than the Ford. Because the Ford has a larger battery pack, it's eligible for larger tax credits that give it that eventual edge in pricing.

A larger battery pack also gives Ford a notable boost in EV range. There's no denying the electric-only range of the C-Max Energi is more impressive than the paltry 10 miles offered in the Prius Plug-In. The battle of EV mode top speed is another solid score for the Ford. The C-Max Energi can hit 85 mph, while the Prius Plug-In tops out at 62 mph before its gasoline-powered engine kicks in. And that's where the numbers once again start to get a little blurry.

Compared to the (non-plug-in) Prius v hybrid wagon (44/40-mpg city/highway), the C-Max Energi's 2.0-liter Atkinson-cycle inline-4 is more fuel-efficient. But that's not the case with the Prius Plug-In Hybrid. In hybrid mode, the Toyota beats the Ford C-Max Energi with economy averages of 51/49-mpg city/highway. Granted, you could argue the C-Max Energi has a body-style that's more aligned with the compact wagon dimensions of the Prius v.

The bragging rights in the plug-in hybrid market appear to sway like the branches of the trees these cars are supposed to be saving.